UNIVERSITY  OF  CALIFORNIA  PUBLICATIONS. 


COLLEGE  OF  AGRICULTURE. 


AGRICULTURAL  EXPERIMENT  STATION. 


FURTHER    EXPERIENCE    IN 


ASPARAGUS  RUST  CONTROL. 


By  RALPH  E    SMITH. 


■-■■■. 


■MHHSh 


BULLETIN   No.   172 

(Berkeley,  CaU,  January,  1906.) 


W.  W.  SHANNON, 


SACRAMENTO 

SUPERINTENDENT    STATE  PRINTING 
1906 


BENJAMIN  IDE  WHEELER,  Ph.D.,  LL.D.,  President  of  the  University. 

EXPERIMENT  STATION  STAFF  (JANUARY,   1906). 

E.  W.  HILGARD,  Ph.D.,  LL.D.,  Director  and  Chemist.     (Absent  on  leave.) 

E.J.  WICKSON,  M.A.,  Acting  Director  and  Horticulturist. 

W.  A.  SETCHELI,,  Ph.D..  Botanist. 

ELWOOD  MEAD,  M.S.,  C.E-,  Irrigation  Engineer. 

C.  W.  WOODWORTH,  M.S.,  Entomologist. 

R.  H.  IvOUGHRIDGE,  Ph.D.,  Agricultural  Geologist  and  Soil  Physicist.     (Soils  and  Alkali.) 

M.  E.  JAFFA,  M.S.,  Assistant  Chemist.     (Foods,  Nutrition.) 

G.  W.  SHAW,  M.A.,  Ph.D.,  Assistant  Chemist.     (Starches,  Oils,  Beet-Sugar.) 

GEORGE  E    COLBY,  M.S.,  Assistant  Chemist.     {Fruits,  Waters,  Insecticides.) 

RALPH  E.  SMITH,  B.S.,  Plant  Pathologist. 

A.  R.  WARD,  B.S.A.,  D.V.M.,  Veterinarian  and  Bacteriologist. 

E.  W.  MAJOR,  B.Agr.,  Animal  Industry. 

E-  H.  TWIGHT,  B.Sc,  Diplonie  E.A.M.,  Viticulturist. 

F.  T.  BIOLETTI.  M.S  ,  Viticulturist. 

WARREN  T.  CLARKE,  B.S.,  Assistant  Entomologist  and  Asst.  Supt.  Farmers'  Institute*. 

H.  M.  HALL,  M.S  ,  Assistant  Botanist. 

GEORGE  ROBERTS,  M.S.,  Assistant  Chemist,  in  charge  of  Fertilizer  Control. 

C    M.  HARING,  D.V.  M.,  Assistant  Veterinarian  and  Bacteriologist. 

ALBERT  M.  WEST,  "B.S.,  Assistant  Plant  Pathologist. 

E.  H.  SMITH,  M.S.,  Assistant  Plant  Pathologist. 

G.  R.  STEWART,  Student  Assistant  in  Station  Laboratory. 
ALICE  R.  THOMPSON,  B.S.,  Assistant  in  Soil  Laboratory. 
D.  L-  BUNNELL,  Clerk  to  the  Director. 


R.  E.  MANSELL,  Foreman  of  Central  Station  Ground  >■ 

JOHN  TUOHY,  Patron,     ) 

r    Tulare  Substation,  Tulare. 
J.  FORRER,  Foreman,        ) 

J.  W.  MILLS,  Pomona,  in  charge  Cooperation  Experiments  in  Southern  California. 

J.  W.  ROPER,  Patron, 


University  Forestry  Station,  Chico. 
HENRY  WIGHTMAN,  In  charge, 

ROYJONES,/,«^(7«,  ) 

\    University  Forestry  Station,  Santa  Monica. 
J.  H.   BARBER,   Foreman,  ) 

VINCENT  J.  HUNTLEY,  Foreman  of  California  Poultry  Experiment  Station,  Petaluma. 


The  Station  publications  (Reports  and  Bulletins),  so  long  as  avail- 
able, will  be  sent  to  any  citizen  of  the  State  on  application. 


FURTHER  EXPERIENCE  IN  ASPARAGUS  RUST  CONTROE 


By   RALPH   E.    SMITH. 


INTRODUCTION  AND  REVIEW  OP  PREVIOUS  WORK. 

During  the  investigation  of  asparagus  rust  in  California,  two  publi- 
cations have  already  been  issued  by  this  Station — Circular  No.  9, 
4 'Report  on  Asparagus  Rust  Investigation,'  and  Bulletin  No.  165, 
" Asparagus  and  Asparagus  Rust  in  California.'  Circular  No.  9, 
published  at  the  close  of  the  first  season's  work,  presents  particularly 
some  observations  of  considerable  practical  value  upon  the  relations 
between  the  occurrence  of  the  rust  and  the  peculiar  features  of  the 
California  climate,  showing  how  a  great  deal  may  be  done  to  check 
the  disease  by  simple  cultural  practices  requiring  no  special  application 
or  treatment.  Various  other  matters  concerning  the  relation  of  the 
crop  to  the  disease  also  receive  attention  in  this  circular. 

Bulletin  No.  165  aims  to  give  quite  a  complete  account  of  the  culture 
of  asparagus  in  California,  particularly  in  relation  to  the  rust.  The 
nature  and  effects  of  the  disease  are  described  at  length,  together  with 
a  full  account  of  two  years'  experiments  in  the  prevention  or  control 
of  the  rust  by  various  methods  of  treatment,  bringing  the  work  up  to 
the  close  of  the  season  of  1904.  In  its  treatment  of  the  nature  and 
mode  of  development  of  the  fungus  causing  the  disease  this  latter 
bulletin  is  intended  to  be  fairly  complete  and  final,  that  side  of  the 
problem  having  been  worked  out  quite  fully  under  the  conditions 
existing  in  all  portions  of  the  State  where  asparagus  is  extensively 
cultivated.  The  nature  of  the  disease,  and  its  relation  to  natural  con- 
ditions, seem  to  require  no  further  investigation  at  present  in  California. 

In  regard  to  methods  of  treatment  for  the  control  of  the  rust  it  may 
fairly  be  said  that  up  to  the  time  of  the  appearance  of  the  disease  in 
California  nothing  effective  and  satisfactory  had  been  developed  in 
other  portions  of  the  country  previously  affected.  Considerable  effort 
had  been  made  in  this  direction  by  a  number  of  State  Experiment 
Stations,  but  the  difficulties  of  the  problem  were  great.  The  cause  of 
the  disease  and  its  general  nature  were  well  understood.     Being  of  a 


4  UNIVERSITY   OF    CALIFORNIA  —  EXPERIMENT    STATION. 

fungous  origin,  spraying  the  plant  with  fungicides  was  the  usual  line 
of  treatment  resorted  to,  and  not  without  more  or  less  success. 

Two  difficulties  in  particular,  however,  kept  such  methods  from  ever 
becoming  completely  satisfactory  or  permanently  successful.  The 
earliest  experimenters  who  attempted  to  find  means  for  controlling  the 
rust  soon  recognized  the  first  of  these  difficulties.  Working  with  the 
Bordeaux  mixture  and  other  similar  liquid  sprays,  they  found  it  im- 
possible to  cover  the  smooth,  glossy  surface  of  the  plant  with  a  uniform 
coating  of  these  substances,  on  account  of  the  tendency  of  the  fungicide 
to  gather  into  drops.  Some  effect  in  favor  of  the  treatment  could  be 
seen,  but  not  enough  to  cover  the  expense  or  save  the  beds  from  severe 
injury.  Sirrine,  of  the  Geneva  (New  York)  Station,  overcame  this 
difficulty  quite  successfully  by  the  addition  of  resin  soap  to  the  spray 
liquid,  by  which  means  asparagus  tops  could  be  thoroughly  covered 
with  the  Bordeaux  mixture.  This  again,  however,  on  account  of  the 
rapid  and  continual  development  of  the  asparagus  tops,  proved  insuf- 
ficient. Unless  sprayed  every  few  days  throughout  a  long  season  the 
fields  soon  outgrow  the  application  and  succumb  eventually  to  the 
destructive  rust. 

To  control  the  disease  at  all  well  with  the  resin-Bordeaux  mixture, 
thorough  spraying  at  least  once  a  week  was  found  necessary— a  course 
which  is  impracticable  on  account  of  the  expense,  and  impossible  in  the 
iarge  California  fields  on  account  of  the  slowness  of  the  operation  and 
enormous  amount  of  liquid  which  would  have  to  be  hauled  about  the 
fields.  In  the  work  of  Sirrine  a  special  spray-outfit  was  devised  for  the 
purpose,  and  at  least  one  machine  for  asparagus  spraying  is  on  the 
market,  but  the  expense  and  time  required  to  keep  down  the  rust  at  all 
completely  by  resin-Bordeaux  spraying  are  so  great  that  growers  gen- 
erally have  given  up  this  treatment  as  being  out  of  the  question  except 
in  a  very  small  way. 

In  California  the  rust  problem  soon  resolved  itself  into  two  somewhat 
distinct  branches— that  of  the  districts  represented  by  Milpitas  and 
Sacramento  City,  and  that  of  the  River  district.  The  former  asparagus 
sections  are  characterized  as  districts  composed  of  numerous  small 
holdings  (5  to  100  acres),  with  rows  planted  close  together  (5  to  7  feet), 
and  subject  to  considerable  dew  in  summer.  The  River  section  has 
large  individual  plantings  (100  to  1,000  acres),  with  rows  8  to  10  feet 
apart,  and  a  dry,  windy  climate  in  summer.  The  question  of  rust  con- 
trol proved  quite  different  in  these  two  sections. 

At  the  beginning  of  the  present  work  in  California,  spray  methods 
such  as  had  been  used  in  the  Eastern  States  were  tested  quite  thor- 
oughly, in  order  to  leave  nothing  undone  which  might  be  of  value  to  the 
asparagus   growers   of  this   State.     During  the   seasons   of   1903   and 


FURTHER   EXPERIENCE   IN   ASPARAGUS   RUST    CONTROL.  5 

1904  spraying  experiments  with  Bordeaux  mixture,  resin-Bordeaux, 
and  other  copper  sprays  were  carried  on  at  Milpitas,  Sacramento,  and 
various  points  in  the  River  section.  The  results  were  practically  the 
same  as  those  obtained  in  other  states.  The  amount  of  rust  could  be 
kept  down  by  very  frequent  applications,  but  even  at  best  the  disease 
could  not  be  controlled  thoroughly  enough  to  prevent  severe  injury,  and 
the  expense  and  time  required  to  obtain  even  indifferent  results  were 
too  great  to  make  the  treatment  practical  or  bring  it  into  general  use. 
The  tops  could  not  be  kept  covered  with  copper  sprays  thoroughly 
enough  to  prevent  the  development  of  the  disease. 

The  idea  then  suggested  itself  that  a  "dust  spray"  treatment  might 
obviate  some  of  the  difficulties  of  the  liquid  method,  requiring  less 
weight  of  material  and  allowing  more  rapid  application.  Various  mix- 
tures of  this  sort,  composed  of  pulverized  bluestone  and  other  copper 
salts  mixed  with  lime,  were  therefore  prepared  and  applied  to  asparagus 
in  various  ways  and  at  different  places.  The  results  with  these  copper- 
dust  sprays  in  controlling  the  rust  were  about  the  same  as  with  the 
liquid  sprays:  not  sufficient  to  make  the  treatment  a  satisfactory  one. 
Some  effect  could  be  obtained,  but  not  enough  to  save  the  crop  or  pay 
for  the  expense. 

Discovery  of  Effects  of  Sulfur.— In  the  experiments  with  dust  sprays 
during  the  season  of  1903,  it  was  found,  quite  unexpectedly,  that  dry 
sulfur  applied  to  asparagus  tops  had  a  decided  effect  in  preventing  the 
development  of  rust.  In  these  experiments  rows  dusted  with  dry  sulfur 
several  times  during  the  season  became  much  less  rusted  than  any 
others.  So  promising  did  this  appear  that  such  treatment  was  urged 
upon  growers  for  1904,  and  over  100  tons  of  sulfur  was  used  in  the 
State  upon  asparagus  during  that  season.  It  may  frankly  be  said  that 
much  of  this  was  wasted  or  applied  without  effect.  Information  was 
jacking  as  to  the  proper  time  and  methods  of  application,  the  best  kind 
of  sulfur  to  use,  how  much  to  put  on,  and  other  practical  details.  Some 
expected  too  much  of  the  treatment,  applying  a  small  amount  of  sulfur 
in  a  careless  manner  after  the  rust  was  well  started,  and  then  being 
disappointed  by  their  poor  success.  Experience  with  the  treatment  was 
also  not  uniform  in  all  the  different  asparagus  districts.  A  full  report 
of  the  experience  of  that  year  will  be  found  in  Bulletin  No.  165,  and 
need  not  be  repeated  here. 

The  most  encouraging  feature  of  the  season's  work  was  the  success  of 
the  growers  at  Sacramento,  who  developed  an  original  modification  of 
the  treatment,  which  gave  absolute  control  of  the  rust  in  the  best-treated 
fields,  though  it  was  abundant  on  all  sides  in  neglected  beds.  Their 
treatment  consisted  in  spraying  with  Bordeaux  mixture,  then  sprinkling 


6  UNIVERSITY   OF   CALIFORNIA— EXPERIMENT   STATION. 

on  dry  sulfur  by  hand  while  the  tops  were  still  wet.  This  was  done, 
first,  within  three  weeks  from  the  time  that  the  tops  came  up  after 
cutting  stopped,  repeated  in  the  latter  part  of  July,  and  followed  by 
an  application  of  sulfur  alone  about  a  month  later.  This  method,  where 
fully  carried  out,  entirely  prevented  the  development  of  any  rust 
during  the  whole  season,  and  was  certainly  the  most  effective  asparagus 
rust  treatment  ever  demonstrated  anywhere.  Progress  Avas  also  made 
during  the  season  in  developing  means  for  applying  sulfur,  and  in  other 
details  of  this  method  of  treatment.  General  experience  demonstrated 
thoroughly — 

That  sulfur  would  keep  the  rust  in  check,  if  properly  applied. 

That  for  satisfactory  results  the  first  application  must  be  made  before 
any  rust  appears. 

That  the  sulfur  must  stay  on  the  tops  and  cover  them  quite  thor- 
oughly, in  order  to  do  much  good. 

Improper  application  in  regard  to  the  last  two  principles  accounted 
in  almost  every  instance  for  failure  of  the  treatment. 

Sulfur  in  Liquid  Sprays.  —  The  success  of  the  dry-sulfur  treatment 
led,  in  1904,  to  some  experiments  with  liquid-sulfur  sprays,  in  order 
to  broaden  the  scope  of  the  work.  It  was  found  that  a  spray  mixture 
made  by  dissolving  sulfur  in  caustic  soda,  with  the  addition  of  resin  or 
whale-oil  soap,  had  some  advantage  in  effect  over  resin-Bordeaux, 
though  open  to  some  of  the  same  objections. 

(See  Bulletin  No.  165,  for  account  of  all  work  up  to  this  point.) 

New  Information  Gained  in  Season  of  1905. 

The  present  bulletin  presents  new  information  in  regard  to  asparagus 
rust  treatment,  obtained  from  the  practical  work  of  various  growers 
during  the  past  season,  and  from  some  special  observations  and  experi- 
ments made  in  connection  with  Mr.  Wm.  Boots,  Jr.,  who  has  been  the 
mainstay  of  this  work  from  the  beginning.  It  seemed  most  necessary 
to  determine  in  particular  the  following  points:  number  of  times  neces- 
sary to  sulfur,  best  times  for  application,  how  much  sulfur  to  use,  what 
kind  of  sulfur  is  best  for  the  purpose,  and  how  to  treat  the  fields  in  the 
River  district  where  there  is  very  little  dew  in  summer  and  the  rust 
appears  late  in  the  season.  The  procedure  and  results  in  a  few  typical 
cases  may  be  described  as  covering  these  points. 

EXPERIENCE  AT  BOOTS    RANCH,  MILPITAS. 

Asparagus  cutting  stopped  at  Milpitas  about  the  first  of  July.  Rust 
was  less  abundant  than  usual  on  uncut  tops  early  in  the  season,  but 
developed  very  vigorously  after  the  beds  grew  up.    In  the  Boots  field 


FURTHER   EXPERIENCE    IN   ASPARAGUS   RUST    CONTROL.  7 

special  efforts  were  made  to  keep  down  wild  growth  about  the  edges, 
which  in  previous  years  had  "caused  a  large  amount  of  infection  early 
in  the  summer.  This  had  a  very  beneficial  effect,  giving  all  portions  of 
the  field  a  chance  to  develop  equally,  except  one  corner  which  bordered 
en  a  badly  rusted  field.  After  the  end  of  the  cutting  season  and  the 
usual  plowing  and  cultivation,  the  field  was  irrigated,  in  order  to 
start  up  as  vigorous  a  growth  of  tops  as  possible.  About  August  1st 
heavy  dews  occurred,  and  the  first  sulfuring  was  started.  Using  the 
seed-sower  arrangement  devised  by  Mr.  Boots,  going  in  every  fifth  row 
(seven  feet  apart),  70  sacks    (110  pounds)    of  sublimed  sulfur  were 


FIG.  1.    Seed-sower,  as  adapted  for  applying  sulfur. 

put  onto  the  75  acres,  in  three  mornings.  About  three  weeks  later 
(August  20  to  25),  a  second  application  was  made.  At  this  time,  going 
m  every  third  row,  60  sacks  of  sulfur  were  put  on.  Mr.  Boots  had,  in 
the  meantime,  improved  on  the  machine  somewhat,  principally  in  the 
sheet-iron  hood  over  the  vent,  which  threw  the  sulfur  more  downward 
into  the  rows,  thus  producing  a  saving  in  material.  After  another  three 
weeks  (September  12  to  15)  the  third  and  last  sulfuring  was  made, 
using  50  sacks  of  sulfur.  Mr.  Boots  had  still  further  improved  upon 
his  machine,  by  broadening  the  hood  and  curving  it  over  more  on  the 
sides  than  is  shown  in  Fig.  1,  with  radiating  flanges  set  in  on  the  under 
side  to  equalize  the  spreading  of  the  sulfur  and  confine  it  somewhat 


b  UNIVERSITY   OF   CALIFORNIA— EXPERIMENT   STATION. 

to  the  three  rows  of  asparagus.     The  sower  was  also  set  over  to  the 
middle  of  the  bed,  and  run  by  a  long  shaft  with  chain  gear  on  both 


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wheels.     This  difference  is  shown  by  comparing  Fig.  1  with  Fig.  39 
of  Bulletin  No.  165.    The  field  was  heavily  irrigated  and  well  cultivated 


FURTHER   EXPERIENCE    IN    ASPARAGUS   RUST    CONTROL. 


9 


during  the  summer,  in  order  to  strengthen  and  force  the  growth  as 
much  as  possible,  irrespective  of  rust  treatment. 


Results.— The  results  of  Mr.  Boots's  work  can  be  most  easily  indi- 
cated by  a  comparison  of  Figs.  2  and  3.    Fig.  2  shows  the  growth  in  the 


10  UNIVERSITY   OF   CALIFORNIA — EXPERIMENT   STATION. 

sulfured  field,  taken  on  October  20,  while  the  other  picture  was  taken 
on  the  same  day  in  a  field  separated  only  by  a  fence  from  the  first,  of 
similar  age  and  on  similar  soil.  All  untreated  fields  in  the  neighborhood 
were  badly  rusted  early  in  September  and  the  tops  black  and  dead  in 
October,  when  these  pictures  were  taken.  As  shown  in  Fig.  3,  there  was 
scarcely  any  sign  of  asparagus  left  on  the  ground  except  a  few  black- 
ened, stunted  stalks.  The  rust  was  never  worse  anywhere  in  its  history 
than  at  Milpitas  this  season,.  The  Boots  field  made  a  fine  growth,  the 
best  in  years  from  the  testimony  of  all  local  observers,  and  remained 
green  until  the  normal  end  of  the  season,  except  for  some  yellowing 
from  insect  attacks.  There  was  not  enough  rust  in  the  field  to  show  any 
effect  upon  the  tops,  except  in  one  corner,  next  the  field  shown  in  Fig.  3. 
This  was  started  somewhat  before  sulfuring  commenced,  and  was  enor- 
mously exposed  to  infection.  The  attack  was  not  severe  even  there,  and 
did  not  spread  out  into  the  field.  The  tops  made  a  good  growth,  even 
in  the  worst  part.  The  condition  of  the  field  as  a  whole  was  equal  to 
that  shown  in  the  figure. 

Expense. — The  cost  of  this  treatment  amounted  to  about  $425  for 
sulfur,  and  $25  for  labor,  or  $6  per  acre  for  the  season's  work  on  75 
acres.  From  the  season's  experience  the  sulfur  bill  can  be  reduced 
to  $300  in  the  future. 

Mr.  Boots  also  grew  a  seed-bed  during  the  season,  producing  as  fine 
a  lot  of  young  plants  as  one  often  sees.  From  the  time  the  seedlings 
appeared  above  ground  until  fall,  he  kept  the  rows  well  sprinkled 
with  sulfur,  and  succeeded  in  keeping  out  all  but  a  trace  of  rust  during 
the  season,  the  plants  making  a  splendid  growth.  This  was  probably 
the  only  bed  of  plants  grown  successfully  in  that  section  since  the  rust 
first  started. 

EXPERIENCE    OF    R.    S.    BARBER,    MILPITAS. 

Mr.  Barber,  who  has  nearly  the  same  acreage  of  asparagus  as  Mr. 
Boots,  is  another  progressive  grower  in  the  Milpitas  district.  The 
treatment  and  condition  of  his  fields  previous  to  1905  have  been  alluded 
to  in  Bulletin  No.  165.  Mr.  Barber's  method  of  applying  sulfur  was 
somewhat  different  from  that  of  Mr.  Boots.  He  had  made  the  machine 
shown  in  Fig.  4,  a  high-bodied,  two-wheeled  truck,  with  a  blacksmith's 
centrifugal  blower  worked  by  hand,  and  a  sheet-iron  hopper,  from 
which  the  sulfur,  as  it  falls  from  the  bottom  into  the  pipe,  is  blown 
through  the  three  arms,  each  opening  over  an  asparagus  row.  The  man 
who  runs  the  bellows  also  turns  a  stirrer  in  the  hopper,  which  pulverizes 
the  sulfur  and  keeps  the  supply  running  down  into  the  outlet.  Several 
of  these  machines  have  been  made  locally  for  asparagus  growers,  and 
one  of  the  "dust  sprayer'1  manufacturing  firms  has  attempted  an 
asparagus   duster   along   somewhat   similar   lines,    using   one   of  their 


FURTHER   EXPERIENCE    IN   ASPARAGUS    RUST    CONTROL. 


11 


machines  with  a  cog-wheel  gear  on  the  wheel,  and  pipes  behind  for 
treating  three  rows.  So  far  as  the  writer  is  informed,  Mr.  "William 
Meek  was  the  originator  of  this  idea. 

This  machine  will  not  throw  nearly  the  amount  of  sulfur  put  on  by 
the  seed-sower  used  by  Mr.  Boots,  and  is  open  to  objection  on  that 
point.  Its  greatest  capacity  produced  only  a  dribble  of  sulfur  on  each 
row.  On  the  other  hand,  less  sulfur  was  required  by  this  method  for 
one  application,  as  it  all  went  on  the  rows,  and  the  machine  could  not 
be  made  to  spread  a  large  amount,  like  the  seed-sower.  The  latter  can 
be  adjusted  to  throw  any  amount,  small  or  great,  but  scatters  the 
material  more  than  the  pipe  arrangement.     In  the  case  of  the  latter, 


FIG.  4.    Sulfur  blower  for  treating  asparagus. 

frequent  applications  were  made  by  Mr.  Barber  during  the  summer — 
four  or  five  in  all— so  that  the  total  amount  of  sulfur  used  was  fully  as 
much  or  greater  than  that  required  in  Mr.  Boots's  method.  This  field 
was  irrigated  and  cultivated  during  the  summer,  and  was  never  allowed 
to  suffer  in  any  way  for  lack  of  care. 

Results. — Mr.  Barber's  results  were  fully  as  satisfactory  as  those  of 
Air.  Boots.  His  asparagus  made  a  beautiful,  heavy  growth,  and  re- 
mained green  until  late  in  fall,  with  no  damage  from  rust.  Nearby 
fields  in  all  directions  which  received  no  treatment  suffered  very 
severely.  Both  these  growers  had  every  reason  to  feel  satisfied  with 
their  efforts. 

Other  Milpitas  growers  used  more  or  less  sulfur  on  asparagus  during 
the  season,  with  results  in  every  case  proportionate  to  the  efforts  put 


12 


UNIVERSITY   OF   CALIFORNIA— EXPERIMENT   STATION. 


forth.    The  futility  of  sulfuring  after  the  rust  becomes  well  developed 
in  the  field  was  shown  here  again,  as  has  been  the  universal  experience. 

SACRAMENTO    EXPERIENCE. 

The  Sacramento  growers  had  reason  to  feel  that  they  had  solved  the 
problem  of  rust  control  from  their  experience  of  1904,  when  the  com- 
bination liquid-spray  and  dry-sulfur  treatment  gave  absolute  control 
of  the  rust.  In  1905  almost  all  of  them  carried  out  the  same  line  of 
treatment,  and  with  results  equal  to  those  of  1904. 

Mr.  E.  Rider  used  sulfur  alone,  as  before,  putting  it  on  with  a  hand 


FIG.  5.  Outfit  for  treating  asparagus  by  Sacramento  method,  consisting  of  pump  and 
barrel  on  one-horse  sled,  one  man  to  pump  and  drive,  two  to  spray  with  liquid, 
and  two  to  apply  sulfur  from  buckets  by  hand. 

blower  on  dewy  mornings,  and  kept  his  fields  green  until  late  fall. 
The  growers  using  the  combination  treatment  made  an  improvement 
on  their  original  method,  adding  whale-oil  soap  to  the  Bordeaux  spray 
as  recommended  in  Bulletin  No.  165.  This  made  a  marked  improvement 
in  sticking  the  sulfur  to  the  tops.  Their  method  of  work  was  that  of 
1904,  using  a  one-horse  sled  between  the  rows,  carrying  a  barrel  and 
pump,  one  man  pumping  and  driving,  one  or  two  spraying,  and  two 
following  close  behind  with  buckets  of  sulfur  (which  had  first  been 
sifted  with  a  flour-sifter),  sprinkling  it  on  by  hand.  Figure  5  illus- 
trates this  method. 

The  work  of  O'Brien  Brothers  is  a  typical  example  of  what  was  done 
at  Sacramento.  These  growers  sprayed  and  sulfured  their  beds  be- 
tween July  15  and  25,  doing  the  work  very  thoroughly  and  carefully. 


FURTHER   EXPERIENCE    IN   ASPARAGUS   RUST    CONTROL. 


13 


On  their  15  acres  of  asparagus  they  used  22  sacks  of  sulfur.  One 
month  later  (August  22)  they  put  on  about  40  sacks  of  sulfur  alone, 
sprinkled  on  by  hand  on  wet  mornings  (3  to  9  a.  m.).  Only  these  two 
applications  were  made  by  these  and  the  other  growers  using  the  same 
method.  It  is  also  worth  noting  that  30  rows  in  the  field  received 
only  the  one  treatment  of  soap-Bordeaux  and  sulfur  in  July,  and 
nothing  further  during  the  season. 

Results.  —  The  results  of  this  treatment  were  as  good  as  in  1904,  the 
rust  control  being  practically  perfect.    The  tops  in  untreated  fields  were 


FIG.  6.    Outfit  for  spraying  asparagus  with  liquid  spray. 

killed  early  and  completely,  rust  was  active  and  abundant  on  all  sides, 
but  all  the  well-treated  beds  kept  green  and  free  from  the  disease.  The 
30  rows  which  had  but  one  treatment  were  particularly  examined  by 
the  writer,  and  found  to  be  as  free  from  rust  as  the  rest  of  the  field. 

Some  spraying  with  Bordeaux  mixture  done  at  Sacramento  in  1905 
had  the  usual  result  of  affecting  the  rust  only  to  a  very  slight  extent. 
The  Olsen  fields  at  Sixteenth  and  Twenty-third  streets,  north  of  the 
railroad,  were  thoroughly  sprayed  by  the  present  owners,  who  originated 
the  outfit  shown  in  Fig.  6  for  the  purpose.  Straddling  one  row,  with 
two  men  standing  on  the  bridge  behind  spraying  three  rows  with  the 
double  nozzles,  and  one  man  to  pump  and  drive,  this  is  the  most  useful 


14  UNIVERSITY   OP   CALIFORNIA— EXPERIMENT   STATION. 

contrivance  for  spraying  asparagus  which  the  writer  has  seen.  The 
outfit  proved  somewhat  top-heavy,  and  would  be  improved  by  having 
the  wheels  farther  apart. 

A  few  of  the  Sacramento  growers  started  the  season  by  spraying 
with  the  Bordeaux  alone,  when  the  majority  were  both  spraying  and 
sulfuring.  The  result  was  thoroughly  typical  of  all  experience  along 
this  line.  All  the  sprayed  fields  began  to  show  rust  abundantly,  while 
those  which  had  sulfur  in  addition,  situated  on  all  sides  of  the  others, 
with  only  fences  or  roads  between,  kept  clean  (as  before  stated)  all 
through  the  season.  The  growers  who  had  used  Bordeaux  alone  then 
made  a  heavy  application  of  sulfur,  and  succeeded  in  preventing  the 
rust  from  attacking  the  later  growth,  though  this  can  not  be  counted 
upon  under  all  circumstances.  In  these  small  fields  with  rows  close 
together  and  very  thick  growth,  a  thorough  treatment  by  hand  gives 
better  results  than  can  be  expected  in  working  on  a  larger  scale. 

Most  of  the  Sacramento  growers  have  decided  upon  the  following 
treatment  for  future  use :  Three  weeks  after  cutting  stops,  start  spray- 
ing with  whale-oil  soap  and  water  (6  pounds  to  50  gallons)  and  dust 
on  iy2  sacks  of  sulfur  per  acre ;  one  month  later  apply  2  sacks  of  sulfur 
per  acre  (on  dewy  mornings).  This  treatment,  from  two  years'  expe- 
rience, is  an  absolute  rust-preventive  in  that  locality. 

EXPERIENCE    IN    THE    RIVER    DISTRICT. 

The  study  of  rust  control  in  the  great  island  and  river  asparagus 
ranches  has  not  reached  the  stage  of  completion  attained  at  Milpitas 
and  Sacramento.  This  is  mostly  due  to  the  fact  that  it  is  still  a  question 
whether  the  cultural  methods  and  ways  of  taking  advantage  of  climatic 
conditions  described  in  Circular  No.  9  and  Bulletin  No.  165  are  not 
sufficient  to  prevent  any  serious  injury  from  rust  in  most  of  these 
regions.  At  such  places  as  Jersey  Island,  Andrus  Island,  Grand  Island, 
the  Pearson  District,  and,  to  nearly  the  same  extent,  Bouldin  Island, 
the  rust  may  be  so  held  in  check  by  keeping  down  all  early  wild  growth 
which  would  allow  the  fungus  to  start,  and  by  keeping  the  fields  exposed 
to  the  full  drying  effect  of  the  prevailing  wind,  that  expensive  methods 
of  fungicidal  applications  (sulfuring,  spraying,  etc.)  have  not  yet 
been  demonstrated  to  be  necessary. 

It  is  still  a  question  in  much  of  this  region  whether  the  slight  attack 
of  rust  late  in  the  season  is  of  any  serious  consequence,  and  whether 
it  is  necessary  or  would  be  profitable  to  try  to  prevent  it.  It  is  an 
enormous  undertaking  to  make  any  thorough  application  to  these 
great  fields  of  hundreds  of  acres.  The  sulfur  treatment  as  practiced  at 
Milpitas  would  be  difficult,  on  account  of  the  distance  apart  of  the 
rows   and   absence   of   dew.      Thorough   preliminary   spraying   with   a 


FURTHER    EXPERIENCE    IN    ASPARAGUS    RUST    CONTROL.  15 

liquid  is  not  very  attractive,  unless  extremely  necessary,  on  account  of 
the  size  of  the  fields.  It  is  quite  certain  that  one  application,  in  August, 
of  the  Sacramento  spray-sulfur  treatment  would  control  the  rust  suf- 
ficiently. Apparatus  can  be  obtained  or  devised  for  doing  this  rapidly 
if  it  proves  necessary,  but  the  latter  is  still  a  question.  Some  experi- 
ments along  this  line  were  made  at  Vorden  during  the  season,  but 
owing  to  the  late  and  slight  development  of  rust  were  not  conclusive. 
Some  sulfuring  was  also  done  there  and  at  Bouldin  Island,  in  the 
latter  instance  with  a  seed-sower,  but  this  was  late  in  the  season  when 
the  rust  had  already  appeared  and  no  very  definite  results  were  seen. 

The  situation,  as  it  looks  to  the  writer,  is  about  this:  At  Milpitas 
and  Sacramento  the  rust  has  been  completely  and  practically  controlled 
by  the  methods  described.  If  not  so  checked  the  disease  ruins  the  beds 
in  a  few  years.  The  method  in  either  case  consists  essentially  in  get- 
ting a  good  coating  of  sulfur  on  the  tops  before  the  rust  appears  and 
keeping  it  there  through  the  rest  of  the  season.  On  the  river  there  is  a 
doubt  whether  this  is  necessary.  If  so,  practical  means  must  be  found 
for  making  the  same  application  and  doing  it  thoroughly,  rapidly,  and 
cheaply.  It  is  simply  a  question  of  making  the  sulfur  stick  to  the  tops 
before  the  time  when  the  rust  usually  appears. 

EASTERN  EXPERIENCE  WITH  SULFUR  TREATMENT. 

Since  the  beginning  of  this  work  in  California,  considerable  interest 
has  been  displayed  in  the  matter  by  asparagus  growers  in  all  parts  of 
the  countrv.  In  climates  with  rain  in  summer  the  writer  has  felt  no 
faith  in  the  success  of  the  dry-sulfur  treatment,  but  has  suggested  the 
possible  value  of  liquid-sulfur  sprays.  Considerably  to  his  surprise, 
however,  Donner  Brothers,  large  asparagus  growers  of  Seabrook,  South 
Carolina,  Avho  have  kept  closely  in  touch  with  this  work,  report  good 
results  from  the  use  of  dry  sulfur.  Mr.  L.  Donner,  writing  under  date 
of  September  23,  1905,  says: 

We  have  made  this  summer  experiments  with  various  kinds  of  fungicides  against 
asparagus  rust,  but  principally  with  sulfur.  We  have  applied  the  latter  in  varying 
quantities  and  at  different  times,  and  have  found  that  if  applied  in  time,  about 
three  weeks  after  the  crop  was  over,  and  continued  with  two  applications  per 
month  through  June,  July,  and  August,  we  can  keep  the  rust  out  effectively.  We 
have  some  beds  now  which  do  not  show  a  sign  of  rust ;  others  where  we  did  not 
sulfur  early  enough  or  were  treated  with   Sal  Bordeaux,  are  badly  rusted. 

Again,   October  23 : 

We  only  applied  sulfur  in  dry  form,  as  we  have  come  to  the  conclusion  that 
application  of  spray  of  any  kind  is  very  expensive,  and  with  our  present  labor 
almost  impossible  to  apply  thoroughly.  We  divided  our  fields  into  patches  and 
gave  different  applications  of  sulfur  on  each,  as  follows  :  One  piece  we  gave  one 
application   per  month,   another   two   applications,   another   one   in   June   and   July, 


16  UNIVERSITY   OF   CALIFORNIA— EXPERIMENT   STATION. 

and  one  June,  July,  and  August,  while  one  piece  was  given  an  application  after 
every  rain.  We  found  that  it  was  absolutely  essential  to  start  early  (that  is, 
within  three  weeks  after  tops  began  to  grow  up),  and  found  that  we  had  to  give  more 
than  one  application  for  the  first  two  or  three  months.  When  once  the  rust  gets 
a  hold  it  is  impossible,  or  at  least  we  found  it  so  this  year,  to  eradicate  or  stop  it. 
Even  in  the  pieces  where  we  applied  the  heaviest  doses  of  sulfur  we  find  some  traces 
of  rust,  especially  at  ends  of  rows.  We  also  find  that  rust  is  developing  as  late  as 
the  present  month,  October,  even  in  parts  which  we  have  kept  clean  of  it  all  through 
the  season.  I  expect  this  late  rust  can  not  do  much  if  any  harm,  still  we  keep  up 
the  sulfur  treatment  and  shall  also  give  an  application  after  the  bushes  are  cut  down. 
We  have  given  all  the  way  from  400  to  1,000  pounds  per  acre,  and  have  applied 
from  50  to  170  pounds  at  a  time. 

From  the  results  of  these  valuable  experiments  of  Donner  Brothers 
it  seems  possible  that  a  practical  dry-sulfur  treatment  might  be  devel- 
oped, even  in  Eastern  States  with  rain  in  the  summer.  We  certainly 
commend  the  matter  to  the  attention  of  growers  and  investigators  in 
those  states,  giving  the  credit  for  this  pioneer  demonstration  to  those 
who  so  enterprisingly  carried  it  out. 

MACHINERY   FOR    APPLYING   DRY    SULFUR. 

The  outfits  which  growers  have  devised  especially  for  this  work  are 
still  in  process  of  development  and  improvement,  and  can  not  fairly  be 
compared  or  criticised.  They  are  all  doing  the  work,  and  are  improving 
from  year  to  year.  For  work  on  a  small  scale  there  is  little  choice  of 
apparatus,  except  in  regard  to  convenience,  cost,  etc.  Anything  which 
will  put  on  sulfur  in  a  dusty  cloud  will  give  successful  results.  Bellows 
and  fan  blowers  of  many  different  kinds,  pepperbox-style  shakers,  shaking 
through  a  coarse  sack,  and  simply  sprinkling  on  by  hand,  have  all  been 
used  successfully  by  different  growers.  Others,  too,  have  made  failures 
of  all  these  methods.  For  larger  work  we  have  the  seed-sower,  the 
outfit  such  as  Mr.  Barber  and  others  used,  various  large-sized  dust- 
sprayers  of  different  makes,  and  anything  else  which  the  ingenious 
mind  may  suggest.  Some  will  do  better  work  than  others,  but  conditions 
vary  in  different  places,  and  the  best  of  them  can  easily  be  used  in  a 
totally  ineffective  manner.  It  is  easy  to  throw  sulfur  into  an  asparagus 
field.  To  cover  the  tops  thoroughly  with  a  uniform  coating  is  quite  a 
different  matter. 

On  general  principles  the  seed-sower  represents  one  type  of  machine, 
and  the  fan  blowers  with  tubes  another.  The  former  throws  out  a 
tremendous  cloud  of  dust,  which  penetrates  everything  and  settles  gently 
down  upon  the  surface.  This  cloud,  by  hoods  and  flange  chutes  on  the 
under  side  of  the  hood,  can  be  considerably  confined  and  directed  toward 
the  rows.  The  farther  apart  the  rows  the  more  difficult  it  becomes  to 
cover  more  than  one  row  thoroughly  with  the  seed-sower.  The  fan 
blowers  send  out  a  small  stream,  which  either  shoots  through  the  tops 
with  considerable  force,  or,  if  carried  through  tubes,  loses  its  force  and 


FURTHER   EXPERIENCE   IN   ASPARAGUS   RUST    CONTROL.  17 

simply  dribbles  down  upon  the  tops  without  spreading  enough  to  cover 
one  row  thoroughly.     This  necessitates  frequent  applications. 

These  remarks  apply  only  to  the  machines  described  as  having  been 
in  use  during  the  season.  Another  season  will  probably  see  all  of  them 
changed  and  improved  more  or  less.  Theoretically  a  contrivance  with 
a  tube  to  each  row  would  be  most  economical,  but  other  factors  come  in. 
Any  practical  machine  must  have  a  large  hopper,  into  which  a  sack  or 
more  of  sulfur  can  be  emptied  directly,  and  power  and  size  enough  to 
throw  out  a  heavy  dust-cloud  into  each  row  which  it  attempts  to  cover, 
and  an  arrangement  for  regulating  the  flow.  It  must  be  remembered 
that  pure  sulfur  is  heavier  and  less  dusty  than  lime,  which  is  the  usual 
basis  of  dust  sprays. 

For  sulfuring  the  large  fields  in  the  islands,  if  such  treatment  proves 
necessary,  it  appears  to  the  writer  that  a  seed-sower  arrangement  closely 
hooded  in  to  cover  one  row  only,  or  else  a  very  large  fan  blower  with 
pipes  to  two  rows,  will  prove  most  desirable.  The  rows  are  too  far 
apart  to  throw  out  the  sulfur  broadcast,  and  the  smaller  dust-sprayers 
will  not  throw  sulfur  enough  for  use  in  these  fields. 

Some  of  these  practical  questions  can  only  be  solved  by  the  growers 
themselves  or  their  mechanics.  The  writer  would  advise  any  one  inter- 
ested in  the  matter  to  go  and  see  the  different  machines  in  the  hands  of 
those  using  them,  and,  if  possible,  study  them  in  operation. 

MANNER  OF  PUTTING  ON  SULFUR. 

This,  as  repeatedly  stated,  is  the  essence  of  the  whole  matter.  The 
sulfur  must  go  on  in  a  dusty,  smoky  cloud,  and  form  a  covering  all 
over  the  growth.  If  the  apparatus  does  not  throw  the  sulfur  properly, 
if  the  sulfur  is  too  coarse,  the  tops  too  dry,  or  the  wind  too  strong,  or  if 
any  other  condition  prevents  the  proper  result,  the  sulfur  will  probably 
be  thrown  away.  If,  therefore,  a  machine  is  used  which  throws  but  a 
small  quantity,  more  frequent  applications  must  be  made.  If  there  is 
no  dew  one  must  either  wait  for  it  or  wet  the  tops  with  whaleoil-soap 
water.  That  kind  of  sulfur  must  be  used  which  will  stick  on  most 
readily.  If  rows  are  missed  with  the  seed-sower  it  must  take  fewer 
at  a  time ;  and  so  every  condition  which  works  against  ideal  results  must 
be  met  and  overcome. 

KIND    OF    SULFUR    TO    USE. 

This  important  subject  has  received  considerable  attention  since  the 
last  bulletin  was  issued.  As  stated  there,  powdered  sulfur  is  on  the 
market  in  three  grades,  disguised  more  or  less  by  various  brand  and 
trade  names.  Ground,  pulverized,  or  flour  of  sulfur  is  sulfur  ore  which 
has  been  more  or  less  purified  by  melting  and  cooling,  and  then  ground 


18 


UNIVERSITY   OF   CALIFORNIA— EXPERIMENT   STATION. 


m  a  mill.  Sublimed  sulfur  is  that  which  has  been  purified  and  brought 
into  extremely  fine,  flaky  particles  by  the  process  known  as  sublimation. 
Flowers  of  sulfur  consists  of  the  very  finest,  lightest  portion  obtained  in 
sublimation. 

It  was  soon  recognized  in  using  sulfur  on  asparagus  that  there  is  a 
great  difference,  both  in  effect  and  mechanical  action,  between  a  coarse, 
sandy,  ground  sulfur,  and  the  sublimed  or  flowers,  though  the  first  is 
considerably  cheaper.  Bulletin  No.  165  urged  the  use  of  the  better 
grades,  but  this  can  be  much  more  strongly  stated  from  the  results  of 
definite  tests  made  this  season.  In  cooperation  with  Mr.  Boots,  using 
his  seed-sower  machine,  tests  were  made  to  determine  the  covering  and 


FIG.  7.    Sacks  (110  pounds  each)  of  flowers  of  sulfur,  sublimed  and  ground  sulfur 

(from  left  to  right). 

sticking  capacity  of  equal  weights  of  high-grade  ground,  sublimed,  and 

flowers  of  sulfur.    Fig.  7  shows  a  sack  of  each— the  flowers  at  the  left, 

the  ground  at  the  right.     These  three  sacks  of  sulfur  represent  a  value, 

or  cost,  of  $45  per  ton,  $40,  and  $33   (f.o.b.  San  Francisco),  or  about 

$2.50  per  sack  for  the  flowers,  $2.20  for  the  sublimed,  and  $1.90  for  the 

ground.     It  is  readily  seen  that  though  equal  in  weight,  the  bulk  is 

directly  proportionate  to  the  cost.     The  first  test  was  made  by  putting 

on  a  sack  of  ground  sulfur  with  the  sower  regulated  at  a  certain  sized 

opening,  then  one  sack  of  each  of  the  others  at  the  same  opening,  noting 

the  area  or  number  of  rows  covered  by  each. 

The  sack  of  ground  sulfur   ($1.90)   covered 1%   acres. 

The  sack  of  sublimed  sulfur   ($2.20)    covered iy2   acres. 

The  sack  of  flowers  of  sulfur    (c  2.50)    covered 2       acres. 

The  cost  per  acre  was  therefore  $1.38  with  ground  sulfur,  $1.47  with 
sublimed,  and  $1.25  with  flowers. 


FURTHER   EXPERIENCE    IN   ASPARAGUS   RUST    CONTROL.  19 

In  this  test,  using  the  same  sized  opening  in  the  machine  for  all,  very 
little  of  the  ground  sulfur  was  left  in  sight  upon  the  tops,  while  the 
others  formed  a  heavy,  very  prominent  coating.  The  finer  sulfur  came 
out  of  the  machine  more  rapidly  than  the  ground,  so  that  the  difference 
in  the  amount  left  on  the  tops  was  much  greater  than  that- in  the  acreage 
covered.  This  being  impossible  to  measure,  another  test  was  made, 
directing  the  operator  to  vary  the  flow  of  sulfur  by  trying  to  put  on  an 
equal  covering  of  each  kind,  letting  each  sack  go  as  far  as  it  would.  In 
this  way: 

The  sack  of  ground  sulfur  covered 1%   acres. 

The   sack   of   sublimed   sulfur    covered 1%   acres. 

The  sack  of  flowers  of  sulfur  covered 2%   acres. 

Even  in  this  test  the  flowers,  spread  over  nearly  twice  as  much  area 
as  the  ground  sulfur,  showed  at  least  twice  as  much  remaining  on  the 
tops  as  the  latter,  which  was  also  greatly  inferior  in  this  respect  to  the 
sublimed. 

The  cost  basis  figures  this  time,  ground  sulfur  $1.30  per  acre,  sublimed 
$1.17  per  acre,  and  the  flowers  $1.00,  at  the  same  time  leaving  twice  as 
much  sulfur  on  the  tops  with  the  better  kinds,  and  in  a  light,  clinging, 
easily  volatilized  condition.  The  difference  is  not  alone  in  fineness,  for 
the  sublimed  and  flowers  cling  even  to  a  smooth,  dry  surface  to  a  con- 
siderable extent,  like  dust  to  a  mirror,  while  a  large  amount  of  the 
ground  sulfur  falls  off  like  sand,  even  from  wet  tops. 

There  can  be  no  possible  question  that  the  finest,  highest-priced 
flowers  of  sulfur  is  by  far  the  cheapest  and  most  effective  for  use  on 
asparagus.    But  great  care  must  be  used  to  get  the  real  thing. 

NUMBER  AND  TIME  OF  APPLICATIONS,  AND  AMOUNT  OF  SULFUR. 

Enough  has  already  been  said  to  cover  these  points.  The  important 
thing  everywhere  has  been  shown  to  be,  to  get  a  good  coating  of  sulfur 
on  the  tops  just  before  the  rust  is  due  to  appear.  At  Milpitas  and 
Sacramento,  and  in  any  place  where  there  is  considerable  dew  in 
summer,  this  makes  the  first  application  necessary  as  soon  as  the  tops 
get  much  growth,  or  in  about  three  weeks  after  cutting  stops.  A  second 
application  one  month  later,  and  a  third  after  another  month,  using 
one  half  a  sack  of  flowers  of  sulfur  per  acre  each  time,  will  give  good 
results.  This  year's  experience  indicates  that  if  all  wild  growth  at 
the  edges  of  the  fields  is  kept  down  closely,  and  there  is  no  rusty  field 
close  by,  two  applications  (the  first  and  the  second)  are  sufficient,  even 
at  Milpitas.  At  Sacramento  it  has  already  been  stated  that  one  heavy 
sulfuring  combined  with  a  soap  spray  was  the  only  treatment  used  on 
part  of  a  field,  with  results  equal  to  those  of  two  applications.     Others 


20  UNIVERSITY   OF   CALIFORNIA— EXPERIMENT   STATION. 

have  used  a  larger  number  of  light  applications  with  equally  good 
results. 

The  point  of  supreme  importance  is  to  begin  early  enough  and  do 
the  work  thoroughly. 

TREATMENT  OF  YOUNG  BEDS. 

The  poorest  results  from  the  dry-sulfur  treatment,  even  when  care- 
fully made,  have  been  in  the  case  of  young  beds  from  one  to  three  years 
of  age,  in  which  the  tops  have  not  yet  grown  thickly  enough  together 
to  catch  and  hold  the  sulfur  well.  In  such  cases  the  writer  would  advise 
a  thorough  treatment  by  the  Sacramento  method,  spraying  with  whale- 
oil  soap,  following  with  an  application  of  sulfur  by  hand.  In  this  way 
the  growth  can  be  thoroughly  covered  with  sulfur,  which  will  not  be 
easily  shaken  or  even  washed  off.  A  few  treatments  of  this  sort  during 
the  season  will  be  found  effective. 

It  is  the  writer's  opinion  that  growers  with  beds  of  any  age  that  are 
not  too  large,  will  do  well  to  follow  this  method  of  rust  control.  It  has 
been  absolutely  effective  wherever  tried. 

KEEPING    DOWN    WILD    GROWTH. 

Each  year's  experience  shows  more  and  more  that  nothing  is  of  so 
great  value  in  rust  control  in  California  as  the  close,  thorough  rooting- 
out  of  every  stalk  of  wild  asparagus  growing  near  the  fields.  The 
stalks  must  not  be  simply  clipped  off  some  distance  above  ground  or  a 
few  left  because  they  are  few.  One  rusty  stalk  at  the  edge  of  the  field, 
even  if  only  a  few  inches  high,  can  make  several  weeks'  difference  in 
the  appearance  of  the  rust. 

IRRIGATION,    CULTURE,   ETC. 

All  that  has  been  said  along  these  lines  in  previous  publications  is 
still  to  be  strongly  emphasized.  The  best  of  rust  treatment  can  not 
make  up  for  lack  of  care. 

ASPARAGUS  CONDITIONS  IN  1905. 

The  crop  of  the  season  in  California  was  a  very  disappointing  one 
to  growers  and  canners.  Many  fields  have  been  badly  injured  by  rust, 
but  aside  from  these  effects  the  cold,  wet  cutting  season,  following 
unseasonably  warm  weather  in  February,  cut  down  the  crop  severely 
in  every  district.  In  fields  protected  from  rust,  or  in  districts  not 
severely  attacked,  the  tops  have  made  a  better  growth  than  for 
several  years,  and  the  prospect  for  next  year's  (1906)  crop  is  excellent. 

Rust  during  the  season  was  as  active  as  ever;  a  considerable  acreage 


FURTHER    EXPERIENCE    IN    ASPARAGUS    RUST    CONTROL.  21 

of  asparagus,  ruined  by  the  disease,  will  soon  be  plowed  out,  and  much 
more  has  suffered  severely.  On  the  river  the  unusually  long  rainless 
season  held  back  the  rust  until  October,  and  kept  it  from  becoming 
severe  in  that  section. 

One  noticeable  feature  of  this  year's  growth  has  been  a  premature 
yellowing  and  dying  of  many  stalks,  without  regard  to  rust.  This  has 
been  commonly  ascribed  to  the  attacks  of  centipedes  in  the  soil,  minute 
creatures  producing  an  injury  which  was  ascribed  to  wire-worms  in 
Bulletin  No.  165.  In  some  cases  examined  by  the  writer,  the  asparagus 
miner  (Agromyza  simplex  Loew)  was  very  abundant  in  the  stems  of 
the  yellow  stalks. 

In  the  Atlantic  States  the  rust  has  been  unusually  prevalent  in  1905, 
according  to  reliable  reports,  showing  that  the  epidemic  there  has  by  no 
means  passed. 

Of  interest  as  a  matter  of  record  is  the  report  of  the  occurrence  of 
asparagus  rust  in  Arizona,  by  Mr.  J.  Thomas  Brown  of  Prescott,  who 
writes  that  they  have  noticed  the  disease  on  beds  in  the  river  bottom 
there  since  1903. 


CALIFORNIA  PUBLICATIONS  AVAILABLE  FOR  DISTRIBUTION. 


REPORTS. 


1896.  Report    of    the    Viticultural    Work    during    the    seasons    1887-93,    with    data 

regarding  the  Vintages  of  1894-95. 

1897.  Resistant    Vines,    their    Selection,    Adaptation,    and    Grafting.      Appendix    to 

Viticultural  Report  for  1896. 

1898.  Partial   Report  of  Vvork  of  Agricultural   Experiment  Station  for  the  years 

1895-96  and  1896-97. 
1900.     Report  of  the  Agricultural  Experiment  Station  for  the  year  1897-98. 

1902.  Report  of  the  Agricultural  Experiment  Station  for  1898-1901. 

1903.  Report  of  the  Agricultural  Experiment  Station  for  1901-1903. 

1904.  Twenty-second  Report  of  the  Agricultural  Experiment  Station  for  1903-1904. 

BULLETINS. 

Reprint.  Endurance  of  Drought  in  Soils  of  the  Arid  Region. 

No.  128.  Nature,  Value,  and  Utilization  of  Alkali  Lands,  and  Tolerance  of  Alkali. 
(Revised  and  Reprint,  1905.) 

131.  The  Phylloxera  of  the  Vine. 

133.  Tolerance  of  Alkali  by  Various  Cultures. 

135.  The  Potato-Worm  in  California. 

137.  Pickling   Ripe   and   Green  Olives. 

138.  Citrus  Fruit  Culture. 

139.  Orange  and  Lemon  Rot. 

140.  Lands  of  the  Colorado  Delta  in  Salton  Basin,  and  Supplement. 

141.  Deciduous  Fruits  at  Paso  Robles. 

142.  Grasshoppers  in  California. 

143.  California  Peach-Tree  Borer. 

144.  The  Peach- Worm. 

145.  The  Red  Spider  of  Citrus  Trees. 

146.  New  Methods  of  Grafting  and  Budding  Vines. 

147.  Culture  Work  of  the  Substations. 

148.  Resistant  Vines  and  their  Hybrids. 

149.  California  Sugar  Industry. 

150.  The  Value  of  Oak  Leaves  for  Forage. 

151.  Arsenical  Insecticides. 

152.  Fumigation  Dosage. 

153.  Spraying  with  Distillates. 

154.  Sulfur  Sprays  for  Red  Spider. 

155.  Directions  for  Spraying  for  the  Codling-Moth. 

156.  Fowl  Cholera. 

157.  Commercial  Fertilizers. 

158.  California  Olive  Oil ;   its  Manufacture. 

159.  Contribution  to  the  Study  of  Fermentation. 

160.  The  Hop  Aphis. 

161.  Tuberculosis  in  Fowls.      (Reprint.) 

162.  Commercial  Fertilizers.     (Dec.  1,  1904.) 

163.  Pear  Scab. 

164.  Poultry  Feeding  and  Proprietary  Foods.      (Reprint.) 

165.  Asparagus  and  Asparagus  Rust  in  California. 

166.  Spraying  for  Scale  Insects. 

167.  Manufacture  of  Dry  Wines  in  Hot  Countries. 

168.  Observations  on  Some  Vine  Diseases  in  Sonoma  County. 

169.  Tolerance  of  the  Sugar  Beet  for  Alkali. 

170.  Studies  in  Grasshopper  Control. 

171.  Commercial  Fertilizers.      (June  30,  1905.) 

CIRCULARS. 

No.  1.  Texas  Fever.  No.   13.     The  Culture  of  the  Sugar  Beet. 

2.  Blackleg.  14.     Practical    Suggestions    for    Cod- 

3.  Hog  Cholera.  ling-Moth      Control      in      the 

4.  Anthrax.  Pajaro  Valley. 

5.  Contagious  Abortion  in  Cows.  15.  Recent  Problems  in  Agriculture. 
7.  Remedies  for  Insects.  What  a  University  Farm  is 
9.  Asparagus  Rust.  For. 

10.  Reading    Course    in    Economic  16.     Notes   on   Seed-Wheat. 

Entomology.  17.     Why     Agriculture     Should     be 

11.  Fumigation  Practice.  Taught  in  the  Public  Schools. 

12.  Silk  Culture. 

Copies  may  be  had  by  application  to  the  Director  of  the  Experiment 
Station,  Berkeley,  California. 


